Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756985AbWK0FHg (ORCPT ); Mon, 27 Nov 2006 00:07:36 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756958AbWK0FHf (ORCPT ); Mon, 27 Nov 2006 00:07:35 -0500 Received: from ebiederm.dsl.xmission.com ([166.70.28.69]:23447 "EHLO ebiederm.dsl.xmission.com") by vger.kernel.org with ESMTP id S1756906AbWK0FGy (ORCPT ); Mon, 27 Nov 2006 00:06:54 -0500 From: "Eric W. Biederman" To: Andrew Morton Cc: , Linux Containers , "Eric W. Biederman" Subject: [PATCH 3/4] sysctl: Simplify ipc ns specific sysctls Date: Sun, 26 Nov 2006 22:05:10 -0700 Message-Id: <11646039151062-git-send-email-ebiederm@xmission.com> X-Mailer: git-send-email 1.4.2.g3cd4f In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5627 Lines: 197 This patch refactors the ipc sysctl support so that it is simpler, more readable, and prepares for fixing the bug with the wrong values being returned in the sys_sysctl interface. The function proc_do_ipc_string was misnamed as it never handled strings. It's magic of when to work with strings and when to work with longs belonged in the sysctl table. I couldn't tell if the code would work if you disabled the ipc namespace but it certainly looked like it would have problems. Signed-off-by: Eric W. Biederman --- kernel/sysctl.c | 106 +++++++++++++++++++++++++------------------------------ 1 files changed, 49 insertions(+), 57 deletions(-) diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 63db5a5..638aa14 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -91,7 +91,9 @@ #ifdef CONFIG_CHR_DEV_SG extern int sg_big_buff; #endif #ifdef CONFIG_SYSVIPC -static int proc_do_ipc_string(ctl_table *table, int write, struct file *filp, +static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp, + void __user *buffer, size_t *lenp, loff_t *ppos); +static int proc_ipc_doulongvec_minmax(ctl_table *table, int write, struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos); #endif @@ -188,6 +190,18 @@ static void put_uts(ctl_table *table, in up_write(&uts_sem); } +#ifdef CONFIG_SYSVIPC +static void *get_ipc(ctl_table *table, int write) +{ + char *which = table->data; + struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns; + which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns; + return which; +} +#else +#define get_ipc(T,W) ((T)->data) +#endif + /* /proc declarations: */ #ifdef CONFIG_PROC_SYSCTL @@ -457,58 +471,58 @@ #ifdef CONFIG_SYSVIPC { .ctl_name = KERN_SHMMAX, .procname = "shmmax", - .data = NULL, - .maxlen = sizeof (size_t), + .data = &init_ipc_ns.shm_ctlmax, + .maxlen = sizeof (init_ipc_ns.shm_ctlmax), .mode = 0644, - .proc_handler = &proc_do_ipc_string, + .proc_handler = &proc_ipc_doulongvec_minmax, }, { .ctl_name = KERN_SHMALL, .procname = "shmall", - .data = NULL, - .maxlen = sizeof (size_t), + .data = &init_ipc_ns.shm_ctlall, + .maxlen = sizeof (init_ipc_ns.shm_ctlall), .mode = 0644, - .proc_handler = &proc_do_ipc_string, + .proc_handler = &proc_ipc_doulongvec_minmax, }, { .ctl_name = KERN_SHMMNI, .procname = "shmmni", - .data = NULL, - .maxlen = sizeof (int), + .data = &init_ipc_ns.shm_ctlmni, + .maxlen = sizeof (init_ipc_ns.shm_ctlmni), .mode = 0644, - .proc_handler = &proc_do_ipc_string, + .proc_handler = &proc_ipc_dointvec, }, { .ctl_name = KERN_MSGMAX, .procname = "msgmax", - .data = NULL, - .maxlen = sizeof (int), + .data = &init_ipc_ns.msg_ctlmax, + .maxlen = sizeof (init_ipc_ns.msg_ctlmax), .mode = 0644, - .proc_handler = &proc_do_ipc_string, + .proc_handler = &proc_ipc_dointvec, }, { .ctl_name = KERN_MSGMNI, .procname = "msgmni", - .data = NULL, - .maxlen = sizeof (int), + .data = &init_ipc_ns.msg_ctlmni, + .maxlen = sizeof (init_ipc_ns.msg_ctlmni), .mode = 0644, - .proc_handler = &proc_do_ipc_string, + .proc_handler = &proc_ipc_dointvec, }, { .ctl_name = KERN_MSGMNB, .procname = "msgmnb", - .data = NULL, - .maxlen = sizeof (int), + .data = &init_ipc_ns.msg_ctlmnb, + .maxlen = sizeof (init_ipc_ns.msg_ctlmnb), .mode = 0644, - .proc_handler = &proc_do_ipc_string, + .proc_handler = &proc_ipc_dointvec, }, { .ctl_name = KERN_SEM, .procname = "sem", - .data = NULL, + .data = &init_ipc_ns.sem_ctls, .maxlen = 4*sizeof (int), .mode = 0644, - .proc_handler = &proc_do_ipc_string, + .proc_handler = &proc_ipc_dointvec, }, #endif #ifdef CONFIG_MAGIC_SYSRQ @@ -2321,46 +2335,24 @@ int proc_dointvec_ms_jiffies(ctl_table * } #ifdef CONFIG_SYSVIPC -static int proc_do_ipc_string(ctl_table *table, int write, struct file *filp, - void __user *buffer, size_t *lenp, loff_t *ppos) +static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp, + void __user *buffer, size_t *lenp, loff_t *ppos) { - void *data; - struct ipc_namespace *ns; - - ns = current->nsproxy->ipc_ns; - - switch (table->ctl_name) { - case KERN_SHMMAX: - data = &ns->shm_ctlmax; - goto proc_minmax; - case KERN_SHMALL: - data = &ns->shm_ctlall; - goto proc_minmax; - case KERN_SHMMNI: - data = &ns->shm_ctlmni; - break; - case KERN_MSGMAX: - data = &ns->msg_ctlmax; - break; - case KERN_MSGMNI: - data = &ns->msg_ctlmni; - break; - case KERN_MSGMNB: - data = &ns->msg_ctlmnb; - break; - case KERN_SEM: - data = &ns->sem_ctls; - break; - default: - return -EINVAL; - } - - return __do_proc_dointvec(data, table, write, filp, buffer, + void *which; + which = get_ipc(table, write); + return __do_proc_dointvec(which, table, write, filp, buffer, lenp, ppos, NULL, NULL); -proc_minmax: - return __do_proc_doulongvec_minmax(data, table, write, filp, buffer, +} + +static int proc_ipc_doulongvec_minmax(ctl_table *table, int write, + struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos) +{ + void *which; + which = get_ipc(table, write); + return __do_proc_doulongvec_minmax(which, table, write, filp, buffer, lenp, ppos, 1l, 1l); } + #endif static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp, -- 1.4.2.rc3.g7e18e-dirty - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/